This invention relates generally to suspended ceiling grid systems for supporting ceiling tiles and the like, and more particularly to means for controlling the vertical components of movement of such a ceiling system as might occur during an earthquake. The compression strut forming the present invention controls such vertical movement of the suspended ceiling without substantial buckling of the supported ceiling tiles as might otherwise occur during an eathquake tremor, thereby preserving the integrity of the suspended ceiling surface.
The present invention is particularly adapted for use in ceiling tile supporting grid systems of the type comprising a plurality of parallel, spaced main grid members which may include cross grid members extending transversely between the main grid members and having end portions interlocking therewith. Such grid members generally are suspended from a conventional ceiling or an overhead support structure framework.
A critical problem encountered in the aforesaid ceiling tile supporting grid structures is to maintain the integrity of the ceiling under sudden movements, such as accompany earthquakes and earthquake tremors. Although the ceiling systems normally resist lateral movement due to engagement with surrounding vertical wall surfaces, the grid systems are subject to upward movement which can result in disorientation of the relative arrangement of grid members. The latter movement results in the ceiling tiles becoming disengaged from a properly mounted position on the grid members with the very likely result of their falling to the floor space below. Not only does such as occurrence present the danger of falling materials but the effectiveness of the suspended ceiling as a fire barrier in such a situation is destroyed and the overhead ceiling and related support structure could thereby be exposed to any related fire which could spread more easily and rapidly throughout the entire structure.